1. Field of the Invention
The present invention relates to an image forming apparatus such as a copier, a multi-function printer (MFP), a printer, or a FAX machine.
2. Description of Related Art
In recent years, due to, for example, an increase in environmental problem consciousness, measures for reducing power consumption have been taken even for an image forming apparatus. For example, in an image forming apparatus forming a toner image, a fixing part including a heater is provided to heat and fix the toner image. Typically, power consumption in the heater accounts for a large portion of power consumed in the image forming apparatus. Thus, an image forming apparatus has been suggested which attempts to provide great power saving effect through power supply control at the fixing part.
Specifically, there is an image forming apparatus including: a data converting section converting document data into bit map data and outputting it; an image forming section forming an image through a xerographic method based on the bit map data; a standby state setting section setting the image forming state at a standby state and releasing the standby state in accordance with release instructions; a predicting section predicting time for the conversion by the data converting section in response to print start instructions; and a warm-up start instructing section, based on a difference between the conversion time predicted by the predicting section and time required for the image forming section to shift to a print-ready state since the release of the standby state, determining timing of releasing the standby state and providing the release instructions to the standby state setting section. The image forming apparatus starts the warm-up at appropriate timing with, for example, a printer with long warm-up time. With this configuration, efforts are made to shorten waiting time until start of printing while reducing power consumption.
Typically, in an image forming apparatus such as a copier or the like, under a given condition (for example, an unused state continues for a while), power supply to part of the configuration is stopped to reduce the power consumption in some cases (shift from a normal mode to a power-saving mode). For example, in the power-saving mode, the power supply to the fixing part including the heater, etc. is stopped.
In the state in which the power consumption has been reduced, at least part of functions in the image forming apparatus is in an unusable state. For example, when the power supply to the fixing part is stopped, a temperature of the fixing part cannot be maintained at a printable temperature. Thus, for example, with user's inputting (for example, operation of a key or a touch panel provided in the MFP) as a trigger, the power supply to a portion where the power supply has been stopped restarts (recovery from the power-saving mode to the normal mode). For example, for the fixing part, the power supply is restarted, and the fixing part is warmed up to the printable temperature through power distribution to the heater.
On the other hand, in the MFP, for a predefined function, a setting screen may be displayed in a wizard format (in an interactive manner). In a case of this wizard format, the user performs inputting on setting screens sequentially displayed. Consequently, omission of a setting can be reduced even if the user is still unfamiliar with the settings and operation.
In making settings in the wizard format, the inputting is performed on the sequentially displayed screens, and thus some time is required for completion of making the settings. Thus, even when warm-up has been started as a result of the recovery from the power-saving mode to the normal mode and then the fixing part has been warmed up to the printable temperature, making the settings in the wizard format have not yet been completed in some cases. Therefore, there arises a problem of waste of power consumed at the fixing part from when the fixing part has been warmed up to the printable temperature to when a job starts in accordance with the settings made in the wizard format after the completion of making the settings.
Attempts made especially in recent image forming apparatuses are shortening time required for warming up the fixing part through, for example, heater power enrichment, temperature increase streamlining, or use of a material with small specific heat. Thus, the time required for the user to perform inputting in the wizard format may become longer.
The image forming apparatus described above does not accept the settings made in the wizard format. Moreover, the image forming apparatus described above starts warming up before data supply to thereby avoid a delay in printing start as a result of not ending the warming up even after completion of data preparation. Therefore, this image forming apparatus cannot cope with a problem of waste of power generated when the settings have been made in the wizard format, that is, the problem of the waste of the power consumed at the fixing part from when the fixing part is warmed up to the printable temperature to when a job starts following the completion of making the settings in the wizard format.